4N26 OPTOCOUPLER Phototransistor

The 4N26 OPTOCOUPLER Phototransistor combines an infrared LED and a silicon phototransistor in a compact dual-in-line package to provide reliable electrical isolation and optical signal transfer for a variety of electronic designs. Collector-Emitter Voltage: 30V, suitable for low to moderate voltage isolation tasks. Current Transfer Ratio (CTR): 20% to 300%, delivering flexible signal amplification across operating conditions. Low Input Current: 10mA, providing energy-efficient operation for control circuits. High Isolation Voltage: 5000 Vrms, offering robust separation between input and output circuits. Response Time: 3µs, enabling moderately fast switching for control and communication systems. Designed to balance isolation performance and switching speed, the 4N26 is a versatile option when designers require dependable protection without sacrificing responsiveness. Its improved CTR helps maintain signal fidelity under varied environmental conditions, reducing the need for additional amplification in many applications. Technology and Integration The device uses a gallium arsenide infrared LED paired with a silicon phototransistor to ensure consistent optical coupling. Its robust internal construction supports compliance with stringent insulation expectations and helps reduce electromagnetic interference between isolated circuits. The compact dual-in-line package simplifies PCB layout and integration into industrial and consumer electronics where space-efficient isolation is required. Typical benefits include protection of microcontrollers and sensitive circuitry from voltage transients and improved noise immunity while preserving signal integrity.